4,801 research outputs found

    A power semiconductor test circuit with reduced power requirements

    Get PDF
    Switching circuit utilizing silicon controlled rectifier reduces input power requirements normally associated with testing power semiconductors in an operational type mode. Circuit alleviates problems of inaccessibility, lack of large amounts of power, physical size of power resistors, wiring, and heat generation

    Simple dynamic electromagnetic radiation detector

    Get PDF
    Detector monitors gamma dose rate at particular position in a radiation facility where a mixed neutron-gamma environment exists, thus determining reactor power level changes. Device also maps gamma intensity profile across a neutron-gamma beam

    Learning About Meetings

    Get PDF
    Most people participate in meetings almost every day, multiple times a day. The study of meetings is important, but also challenging, as it requires an understanding of social signals and complex interpersonal dynamics. Our aim this work is to use a data-driven approach to the science of meetings. We provide tentative evidence that: i) it is possible to automatically detect when during the meeting a key decision is taking place, from analyzing only the local dialogue acts, ii) there are common patterns in the way social dialogue acts are interspersed throughout a meeting, iii) at the time key decisions are made, the amount of time left in the meeting can be predicted from the amount of time that has passed, iv) it is often possible to predict whether a proposal during a meeting will be accepted or rejected based entirely on the language (the set of persuasive words) used by the speaker

    Economic Growth With Optimal Public Spending Compositional

    Get PDF
    This paper uses a one-sector, endogenous growth model to study optimal composition between public investment and consumption in government expenditure and its relationships with economic growth. Assuming a benevolent government which maximizes a representative household’s lifetime utilities, the paper determines the unique, interior public investment share in government’s budgets, which is determined by policy and structural parameters. It finds that the conventional determinants of economic growth now generate stronger growth effects, via their indirect impacts upon optimal public spending composition. The effects emerge from raising the marginal utility of private consumption, relative to the marginal utility of public consumption, thereby inducing public investment and increasing economic growth. Our quantitative results suggest that the growth effect is sizable. The large growth effect via optimal public investment in our model has implications to East Asian economic growth miracles where public investment share and economic growth are both higher than other area’s countries.public consumption, public investment, economic growth

    The role of fuel cells in NASA's space power systems

    Get PDF
    A history of the fuel cell technology is presented and compared with NASA's increasing space power requirements. The role of fuel cells is discussed in perspective with other energy storage systems applicable for space using such criteria as type of mission, weight, reliability, costs, etc. Potential applications of space fuel cells with projected technology advances were examined

    Factor Taxation and Labor Supply In A Dynamic One-Sector Growth Model

    Get PDF
    This paper studies a class of AK-type growth models with public capital stock and elastic labor supply. The government taxes both factor incomes and conduct expenditure. To rationalize the taxation, government expenditure affects the productivity of private sectors. It shows the existence of a unique balanced-growth path, near which there is only a transitional dynamic path leading the economy toward it. While a higher capital tax rate reduces economic growth in the short run, the long-term growth effect is ambiguous, and this long-term growth effect remains ambiguous even if the level of tax rate is larger than the degree of government externality. A higher labor income tax rate has equally ambiguous growth effects both in the short and long runs. However, if the intertemporal elasticity of substitution for labor supply is small enough, a higher labor tax rate always lowers economic growth in the long run, despite the existence of productive government taxation.taxation, infrastructures, economic growth, transitional dynamics

    A survey on tasks performed in eldercare

    Get PDF
    In the Netherlands, a vast increase of the expenses on eldercare is expected for the future. Currently, an IT system is under development that aims to assist care providers with their tasks in providing care services. Before such a system can be used in practice, insight is needed on the current work situation in eldercare. This paper presents interview surveys on tasks currently performed by professionals in two nursing houses. Both the professional population and details on how it spends its time are described. Little room is observed for automating tasks in nursing and/or caring houses

    Cellular and Secretory Proteins of the Salivary Glands of \u3cem\u3eSciara coprophila\u3c/em\u3e During the Larval-pupal Transformation

    Get PDF
    The cellular and secretory proteins of the salivary gland of Sciara coprophila during the stages of the larval-pupal transformation were examined by electrophoresis in 0.6 mm sheets of polyacrylamide gel with both SDS-continuous and discontinuous buffer systems. After SDS-electrophoresis, all electrophoretograms of both reduced and nonreduced proteins from single glands stained with Coomassie brilliant blue revealed a pattern containing the same 25 bands during the stages of the larval-pupal transformation. With the staining procedures used in this study, qualitative increases and decreases were detected in existing proteins and enzymes. There was no evidence, however, for the appearance of new protein species that could be correlated with the onset of either pupation or gland histolysis. Electrophoretograms of reduced samples of anterior versus posterior gland parts indicated that no protein in the basic pattern of 25 bands was unique to either the anterior or posterior gland part. Electrophoretograms of reduced samples of secretion collected from either actively feeding or cocoon -building animals showed an electrophoretic pattern containing up to six of the 25 protein fractions detected in salivary gland samples, with varied amounts of these same six proteins in electrophoretograms of secretion samples from a given stage. Zymograms of non-specific esterases in salivary gland samples revealed a progressive increase in the amount of esterase reaction produce in one major band and some decrease in the second major band during later stages of the larval-pupal transformation
    • …
    corecore